Little Long Lake
St. Louis County, Minnesota322 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Little Long Lake. Here is what has been measured.
- Impaired · Mercury
- 45 ft max depth
- Public access
- Limited data
Little Long Lake in St. Louis County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 21 ft visibility. Maximum depth: 45 ft. Surface area: 322.24 acres.
Minnesota DNR's Standard Survey on August 15, 2022 caught 20.00 walleye per gill net at Little Long Lake. Length samples in the latest survey that recorded them ran 7–28 inches. DNR survey details →
Little Long Lake is a 322-acre lake in St. Louis County, Minnesota with a maximum depth of 45 feet. Overall water quality is declining over recent sampling years. The lake supports 11 documented fish species including black crappie, bluegill, and green sunfish. Public access is available with 2 public boat landings.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-11-05. Methodology: how these readings are compared.
Little Long Lake covers about 320 acres in St. Louis County. It has 2 public boat landings, so a lakefront rental is not the only way to get a boat on the water. The median ice-out date is April 28, which is when the open-water season begins. Vrbo is where to look for cabins and lake homes around Little Long Lake, and Booking.com and Expedia search hotels near the lake for your dates.
What Little Long Lake is good for
From access and monitoring records, not editorial picks.
- Clear water21 ft of visibility
- Boat launch2 documented ramps
- Fishing11 species recorded
- Ice seasonIce-out around Apr 28
- Deep water45 ft surveyed max depth
Swimming conditions
No readingLimited data
Nutrient and algae readings are not a swimming clearance. Little Long Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury. Check local advisories before you swim.
Whether Little Long Lake is safe to swim in today is a call for the Minnesota Pollution Control Agency and the Minnesota DNR and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Little Long Lake
These are the measurements Minnesota PCA publishes for Little Long Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Crystal clear, you can see 21 ft down. TSI 33.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 21ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | No reading The nutrient that most limits algae growth in freshwater. More phosphorus, more algae potential. | |
| Chlorophyll-a (algae) | No reading The green pigment in algae — a direct measure of how much algae is in the water. | |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 33 | Oligotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Low nutrients, clear water. No reading is a swimming clearance.
Ask about Little Long Lake
Answers come straight from the public measurements and survey records on this page.
Minnesota DNR's Standard Survey on August 15, 2022 caught 20.00 walleye per gill net at Little Long Lake. Length samples in the latest survey that recorded them ran 7–28 inches.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Little Long Lake’s water-quality measurements separately, and the water-quality trend over 6 years of monitoring is declining. Catch rate is not a swim clearance and is not a weekly bite report.
DNR Fisheries Survey Summary
10 surveys on file from MN DNR Fisheries. Most recent: 2025-08-01 (Targeted Survey).
10 surveys on file · most recent 2025-08-01 (Targeted Survey)
| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| Bluegill | 46.78 | 3–7 in 2022-08-15 | 0.1 lb |
| Smallmouth Bass | 17.15 | 5–19 in 2022-08-15 | 0.96 lb |
| Tullibee (Cisco) | 10.16 | 17 in 2004-06-14 | 1.42 lb |
| Walleye | 6.90 | 7–28 in 2022-08-15 | 3.29 lb |
CPUE = catch per unit effort, fish caught per net per set in a standardised survey. It measures abundance, not size, and is not a weekly bite report.
Length Distributions
Number of fish caught at each inch class in the most recent survey that recorded lengths. Red dashed line marks an approximate trophy threshold for that species.
Bluegill
Smallmouth Bass
Tullibee (Cisco)
Walleye
From the 2025-08-01 survey
Temperature and dissolved oxygen measurements were collected from the deepest basin in Little Long Lake on August 1st, 2025. This was done to evaluate the quantity and quality of cold, oxygenated water (i.e., oxythermal habitat) available to Cisco, also known as Tullibee, the most sensitive coldwater species present…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Little Long Lake. 4 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — Little LongFisheries Lake Survey · MN DNR LakeFinder
- —Aquatic Plant Report — Little Long (1892)Aquatic Plant Report · MN DNR LakeFinder
- —Fish Stocking History — Little LongFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — Little LongPublic Water Access Sites · MN DNR LakeFinder
Lake Details
Max depth
45 ft
Surface area
322 acres
Shoreline
6.5 mi
Littoral zone
24%
Share shallower than 15 ft
Public access
Yes
Listed by Minnesota PCA
Lake Size & Watershed
Watershed (drainage) area
1 sq mi
HydroLAKES / HydroSHEDS
Elevation
1,414 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Shagawa Lake (Northwest)Public
- Little Long LakePublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Stays via Stay22
Stays near Little Long Lake
Compare lakeside cabins, hotels, and vacation rentals near Little Long Lake in St. Louis County, Minnesota — live availability and prices for your trip. Switch the map to Satellite to see the lake and how close each stay is to the water.
Top-rated places to stay near Little Long Lake
Prices for Oct 9–11, 4 adults. Change dates on the map below.
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Planning a whole trip? See where to stay at Minnesota’s top lakes →
Follow Little Long Lake’s readings
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Fish Species
Click a species to see every lake where it is documented.
Fishing Little Long Lake
- → Little Long Lake fishing: DNR survey catch rates, species & stocking
- → Little Long Lake fishing forecast & best times (species outlook + 14-day solunar calendar)
- → Little Long Lake fishing regulations (limits, seasons, special rules)
- → Is it safe to eat fish from Little Long Lake? (mercury & PFAS guide)
Water Quality Trend: Worsening
Based on 6 years of monitoring (2020–2025).
Water clarity
Worsening6 years
Ice season
Typical ice-out
Apr 28
Earliest Apr 16, 2006 · Latest May 13, 2022
Typical ice-in
Nov 29
Earliest Nov 19, 2014 · Latest Dec 6, 2022
Most recent ice-out
May 9
2023
22 observations · Minnesota PCA ice records
EPA Impairment Status
Little Long Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 4A).
Causes of impairment
Designated uses not supporting: Fish consumption.
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit MN69-0066-00 · Official waterbody report
Nearby Lakes in St. Louis County
Frequently asked questions about Little Long Lake
Where is Little Long Lake?
- Little Long Lake is a lake in St. Louis County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Little Long Lake?
- Little Long Lake in St. Louis County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 21 ft visibility. Maximum depth: 45 ft. Surface area: 322.24 acres.
Is Little Long Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Little Long Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury. Check local advisories before you swim.
How deep is Little Long Lake?
- Little Long Lake has a maximum depth of 45 feet. The lake covers 322.24 acres.
What fish are in Little Long Lake?
- Fish species found in Little Long Lake include black crappie, bluegill, green sunfish, largemouth bass, northern pike, rainbow smelt, rock bass, smallmouth bass, walleye, white sucker, yellow perch. Little Long Lake is located in St. Louis County, Minnesota.
What did the DNR fisheries survey find at Little Long Lake?
- Minnesota DNR's Standard Survey on August 15, 2022 caught 20.00 walleye per gill net at Little Long Lake. Length samples in the latest survey that recorded them ran 7–28 inches. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Little Long Lake’s water-quality measurements separately, and the water-quality trend over 6 years of monitoring is declining. Catch rate is not a swim clearance and is not a weekly bite report.
When does Little Long Lake thaw?
- Little Long Lake typically has ice-out around Apr 28. Ice typically forms around Nov 29. The open water season is approximately 215 days.
Are there boat ramps on Little Long Lake?
- Little Long Lake has 2 documented boat landings in the USGS National Boat Ramps inventory. Named access points include Shagawa Lake (Northwest), Little Long Lake. Public access is listed as yes.
Can I fish at Little Long Lake?
- Little Long Lake has 2 documented boat landings in the USGS National Boat Ramps inventory. Seasons, size and bag limits, and whether you need a license are set by Minnesota's fish and wildlife agency, so check its current regulations before you go.
Explore Little Long Lake across LakeQuality
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Where this data comes from
44 measurements from 4 monitoring stations, 2020–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA44 samples · 2020–2025
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by Two Reagent Colorimetry
- 10200 H ~ Chlorophyll a-b-c Determination
Monitoring station identifiers (4)
EPA condition classes from the National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See where the data comes from and data sources.
Other records on this page
Impairment status from EPA ATTAINS 303(d) database
Lake size & watershed from HydroLAKES (HydroSHEDS)
Lake details from Minnesota DNR LakeFinder
Named boat-access points from the USGS National Boat Ramps inventory
Ice data from Minnesota DNR Climate